Symptoms

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Most people with viral encephalitis have either no symptoms or mild flu-like symptoms, such as the following:

Headache

Fever

Aches in muscles or joints

Fatigue or weakness

More-serious cases require prompt medical care. Additional signs and symptoms of more serious encephalitis may include the following:

Confusion, agitation or hallucinations

Seizures

Loss of sensation or paralysis in certain areas of the face or body

Muscle weakness

Double vision

Perception of foul smells, such as burned meat or rotten eggs

Problems with speech or hearing

Loss of consciousness

Signs and symptoms in infants and young children may also include:

Bulging in the soft spots (fontanels) of the skull in infants

Nausea and vomiting

Body stiffness

Inconsolable crying

Poor feeding or not waking for a feeding

Irritability

When to see a doctor

Get immediate care if you or someone you know is experiencing any of the symptoms associated with more-severe cases of encephalitis. Severe headache, fever and altered consciousness require urgent care.

Infants and young children with any signs or symptoms of encephalitis should receive urgent care.

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